1. Field of the Invention
The present invention relates to an inspection apparatus that inspects top and bottom surfaces of a substrate, such as a wafer.
Priority is claimed on Japanese Patent Application No. 2007-130196, filed May 16, 2007, the content of which is incorporated herein by reference.
2. Description of Related Art
In a semiconductor manufacturing process in the related art, it is known that visual inspection is performed by visual observation or imaging using an imaging device in order to check foreign matter adhering to a surface of a substrate, such as a wafer, film unevenness at the time of application of a resist, failure in exposure performed by an exposure apparatus, and the like. Examples of visual inspection include macro inspection for performing macroscopic inspection and micro inspection for performing enlarged observation using a microscope.
Here, an example of a visual inspection apparatus that performs macro inspection is disclosed in Japanese Unexamined Patent Application Publication No. 2006-170622. The visual inspection apparatus has a substrate holding unit, and a mechanism for performing rotation and rocking of a substrate is provided in the substrate holding unit. An illuminating device that illuminates a substrate is provided above the substrate holding unit. An inspector observes the substrate surface illuminated by the illuminating device by visual observation or using an imaging device. The visual inspection apparatus is used to record a result of visual inspection or share information on defects and the like in the case when a plurality of inspectors are present and is disposed such that an optical axis of an imaging device is substantially equal to the observation position of an inspector. Accordingly, observation and recording corresponding to an observer's observation may be performed.
Moreover, in recent years, it has also been desired to inspect a bottom surface of a substrate. An example of a visual inspection apparatus capable of observing a bottom surface of a substrate is disclosed in Japanese Unexamined Patent Application Publication No. 10-92887. The visual inspection apparatus includes a holding arm for holding the peripheral edge of the substrate, and a rotary shaft is provided at a base end of the holding arm. When the holding arm is disposed in the substantially horizontal direction, an observer can inspect a top surface of a substrate visually. When observing a bottom surface of the substrate, the holding arm is made to move upward by rotation of the rotary axis until the bottom surface of the substrate faces the observer.